The invention relates to a recording and/or playback apparatus having a device for stopping or changing over the transport of a record carrier when an apparatus component, which rotates only during record-carrier transport, is stationary. Magnetic tape recorders are a common example of such apparatus and for simplicity the invention will be described in connection with such recorders, but without limiting application or scope of the claimed invention. This device comprises an eccentric drive member and an actuating member, which can both be driven uniformly and continuously by a motor of the apparatus, the drive member performing a rotary movement and being adapted to cooperate with a pivotably journalled lever. In its turn the lever is connected to the apparatus component through a friction coupling, which exerts a torque on the lever while the component is rotating normally so as to keep the lever positioned against the drive member, so that the lever oscillates pivotally when the apparatus component rotates and is set to a stationary position by the drive member when the apparatus component is stationary. The actuating member performs a periodic movement, from which a control function such as the stop or change-over operation for the record carrier drive can be derived by the actuation of a switching device through the actuating member when the lever is in the stationary position only.
Such apparatus is described in German Auslegeschrift 1,952,842, to which U.S. Pat. No. 3,608,845 corresponds. The operation of the device for stopping or changing over the record carrier drive in this apparatus is based on the fact that the relative movements of the drive member, of the actuating member and of the lever are coordinated in such a way that the actuating member can actuate the switching device only if the lever is in a stationary position when the apparatus component is stationary, and otherwise cannot perform its function. In this known apparatus the drive member and the actuating member are mounted on a flywheel which can be driven by the motor of the apparatus, so that during operation of the apparatus the lever, which is held against the drive member through the action of the friction coupling, is continuously in operative connection with the flywheel. The flywheel being connected directly to the drive spindle for the record carrier transport in the usual manner, this may give rise to an undesired influence on the record carrier transport, which manifest itself as a fluctuation, because as is known such a drive system is very sensitive, in particular if only smaller flywheels can be used for reasons of weight or space.